At the invitation of the School of Atmospheric Science, Professor Klaus Schäfer from Karlsruher Institute of Technology (KIT) paid a visit to CUIT and delivered an academic lectures entitled Air quality-meteorology and chemistry, on October 21. Prof. Schäfer analyzed the effects of air pollutants emission in Beijing and Augsburg on the atmosphere and obtained the spatial distribution and diurnal variation of pollutants. Based on the study of the distribution of air pollution sources in Beijing, he found the causes and regular pattern of haze formation. Lastly, the relationship between air quality and mineral dust in Beijing was numerically simulated. His lecture gave the students a deeper understanding of the significance of polluted meteorology.